rtnetlink.rar_For Real

/* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Routing netlink socket interface: protocol independent part. * * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Fixes: * Vitaly E. Lavrov RTA_OK arithmetics was wrong. */ #include <linux/errno.h> #include <linux/module.h> #include <linux/types.h> #include <linux/socket.h> #include <linux/kernel.h> #include <linux/timer.h> #include <linux/string.h> #include <linux/sockios.h> #include <linux/net.h> #include <linux/fcntl.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/interrupt.h> #include <linux/capability.h> #include <linux/skbuff.h> #include <linux/init.h> #include <linux/security.h> #include <linux/mutex.h> #include <linux/if_addr.h> #include <linux/if_bridge.h> #include <linux/if_vlan.h> #include <linux/pci.h> #include <linux/etherdevice.h> #include <asm/uaccess.h> #include <linux/inet.h> #include <linux/netdevice.h> #include <net/switchdev.h> #include <net/ip.h> #include <net/protocol.h> #include <net/arp.h> #include <net/route.h> #include <net/udp.h> #include <net/sock.h> #include <net/pkt_sched.h> #include <net/fib_rules.h> #include <net/rtnetlink.h> #include <net/net_namespace.h> struct rtnl_link { rtnl_doit_func doit; rtnl_dumpit_func dumpit; rtnl_calcit_func calcit; }; static DEFINE_MUTEX(rtnl_mutex); void rtnl_lock(void) { mutex_lock(&rtnl_mutex); } EXPORT_SYMBOL(rtnl_lock); void __rtnl_unlock(void) { mutex_unlock(&rtnl_mutex); } void rtnl_unlock(void) { /* This fellow will unlock it for us. */ netdev_run_todo(); } EXPORT_SYMBOL(rtnl_unlock); int rtnl_trylock(void) { return mutex_trylock(&rtnl_mutex); } EXPORT_SYMBOL(rtnl_trylock); int rtnl_is_locked(void) { return mutex_is_locked(&rtnl_mutex); } EXPORT_SYMBOL(rtnl_is_locked); #ifdef CONFIG_PROVE_LOCKING int lockdep_rtnl_is_held(void) { return lockdep_is_held(&rtnl_mutex); } EXPORT_SYMBOL(lockdep_rtnl_is_held); #endif /* #ifdef CONFIG_PROVE_LOCKING */ static struct rtnl_link *rtnl_msg_handlers[RTNL_FAMILY_MAX + 1]; static inline int rtm_msgindex(int msgtype) { int msgindex = msgtype - RTM_BASE; /* * msgindex < 0 implies someone tried to register a netlink * control code. msgindex >= RTM_NR_MSGTYPES may indicate that * the message type has not been added to linux/rtnetlink.h */ BUG_ON(msgindex < 0 || msgindex >= RTM_NR_MSGTYPES); return msgindex; } static rtnl_doit_func rtnl_get_doit(int protocol, int msgindex) { struct rtnl_link *tab; if (protocol <= RTNL_FAMILY_MAX) tab = rtnl_msg_handlers[protocol]; else tab = NULL; if (tab == NULL || tab[msgindex].doit == NULL) tab = rtnl_msg_handlers[PF_UNSPEC]; return tab[msgindex].doit; } static rtnl_dumpit_func rtnl_get_dumpit(int protocol, int msgindex) { struct rtnl_link *tab; if (protocol <= RTNL_FAMILY_MAX) tab = rtnl_msg_handlers[protocol]; else tab = NULL; if (tab == NULL || tab[msgindex].dumpit == NULL) tab = rtnl_msg_handlers[PF_UNSPEC]; return tab[msgindex].dumpit; } static rtnl_calcit_func rtnl_get_calcit(int protocol, int msgindex) { struct rtnl_link *tab; if (protocol <= RTNL_FAMILY_MAX) tab = rtnl_msg_handlers[protocol]; else tab = NULL; if (tab == NULL || tab[msgindex].calcit == NULL) tab = rtnl_msg_handlers[PF_UNSPEC]; return tab[msgindex].calcit; } /** * __rtnl_register - Register a rtnetlink message type * @protocol: Protocol family or PF_UNSPEC * @msgtype: rtnetlink message type * @doit: Function pointer called for each request message * @dumpit: Function pointer called for each dump request (NLM_F_DUMP) message * @calcit: Function pointer to calc size of dump message * * Registers the specified function pointers (at least one of them has * to be non-NULL) to be called whenever a request message for the * specified protocol family and message type is received. * * The special protocol family PF_UNSPEC may be used to define fallback * function pointers for the case when no entry for the specific protocol * family exists. * * Returns 0 on success or a negative error code. */ int __rtnl_register(int protocol, int msgtype, rtnl_doit_func doit, rtnl_dumpit_func dumpit, rtnl_calcit_func calcit) { struct rtnl_link *tab; int msgindex; BUG_ON(protocol < 0 || protocol > RTNL_FAMILY_MAX); msgindex = rtm_msgindex(msgtype); tab = rtnl_msg_handlers[protocol]; if (tab == NULL) { tab = kcalloc(RTM_NR_MSGTYPES, sizeof(*tab), GFP_KERNEL); if (tab == NULL) return -ENOBUFS; rtnl_msg_handlers[protocol] = tab; } if (doit) tab[msgindex].doit = doit; if (dumpit) tab[msgindex].dumpit = dumpit; if (calcit) tab[msgindex].calcit = calcit; return 0; } EXPORT_SYMBOL_GPL(__rtnl_register); /** * rtnl_register - Register a rtnetlink message type * * Identical to __rtnl_register() but panics on failure. This is useful * as failure of this function is very unlikely, it can only happen due * to lack of memory when allocating the chain to store all message * handlers for a protocol. Meant for use in init functions where lack * of memory implies no sense in continuing. */ void rtnl_register(int protocol, int msgtype, rtnl_doit_func doit, rtnl_dumpit_func dumpit, rtnl_calcit_func calcit) { if (__rtnl_register(protocol, msgtype, doit, dumpit, calcit) < 0) panic("Unable to register rtnetlink message handler, " "protocol = %d, message type = %d\n", protocol, msgtype); } EXPORT_SYMBOL_GPL(rtnl_register); /** * rtnl_unregister - Unregister a rtnetlink message type * @protocol: Protocol family or PF_UNSPEC * @msgtype: rtnetlink message type * * Returns 0 on success or a negative error code. */ int rtnl_unregister(int protocol, int msgtype) { int msgindex; BUG_ON(protocol < 0 || protocol > RTNL_FAMILY_MAX); msgindex = rtm_msgindex(msgtype); if (rtnl_msg_handlers[protocol] == NULL) return -ENOENT; rtnl_msg_handlers[protocol][msgindex].doit = NULL; rtnl_msg_handlers[protocol][msgindex].dumpit = NULL; return 0; } EXPORT_SYMBOL_GPL(rtnl_unregister); /** * rtnl_unregister_all - Unregister all rtnetlink message type of a protocol * @protocol : Protocol family or PF_UNSPEC * * Identical to calling rtnl_unregster() for all registered message types * of a certain protocol family. */ void rtnl_unregister_all(int protocol) { BUG_ON(protocol < 0 || protocol > RTNL_FAMILY_MAX); kfree(rtnl_msg_handlers[protocol]); rtnl_msg_handlers[protocol] = NULL; } EXPORT_SYMBOL_GPL(rtnl_unregister_all); static LIST_HEAD(link_ops); static const struct rtnl_link_ops *rtnl_link_ops_get(const char *kind) { const struct rtnl_link_ops *ops; list_for_each_entry(ops, &link_ops, list) { if (!strcmp(ops->kind, kind)) return ops; } return NULL; } /** * __rtnl_link_register - Register rtnl_link_ops with rtnetlink. * @ops: struct rtnl_link_ops * to register * * The caller must hold the rtnl_mutex. This function should be used * by drivers that create devices during module initialization. It * must be called before registering the devices. * * Returns 0 on success or a negative error code. */ int __rtnl_link_register(struct rtnl_link_ops *ops) { if (rtnl_link_ops_get(ops->kind)) return -EEXIST; /* The check for setup is here because if ops * does not have that filled up, it is not possible * to use the ops for creating device. So do not * fill up dellink as well. That disables rtnl_dellink. */ if (ops->setup && !ops->dellink) ops->dellink = unregister_netdevice_queue; list_add_tail(&ops->list, &link_ops); return 0; } EXPORT_SYMBOL_GPL(__rtnl_link_register); /** * rtnl_link_